岩石峰后强度参数演化实用新模型研究

A new practical model for the evolution of post-peak strength parameters of rocks

围绕岩石峰后强度参数演化规律及实用模型问题开展研究。从公开出版文献中收集32种岩石三轴压缩试验结果,将峰后软化段应力-应变曲线简化为直线,基于Mohr-Coulomb准则,研究分析不同种类岩石峰后强度参数的一般性演化规律,并基于标准化塑性内变量,建立强度参数演化实用新模型。将所建强度参数演化模型嵌入ABAQUS中,用于模拟岩石峰后应变软化过程,并与多种岩石三轴压缩试验结果进行对比,显示计算得到的峰后应力-应变曲线与试验曲线基本符合,表明所建模型正确。所建模型形式简单、参数少、适用性广,可望在实际工程变形、稳定计算分析中得到广泛应用,研究具有理论价值和工程实用价值。

This paper focuses on the evolution of rock post-peak strength parameters and practical models.The tri-axial compression test results of 32 kinds of rocks are collected from published literatures,and the stress-strain curve in the post-peak softening stage is simplified to a straight line.Based on the Mohr-Coulomb criterion,the general evolution laws of the post-peak strength parameters of different kinds of rocks are studied and analyzed,and a new practical strength parameter evolution model is established based on standardized plastic internal variables.The established strength parameter evolution model is then embedded in ABAQUS to simulate the post-peak strain softening process of rocks.The results of the tri-axial compression tests of various rocks are used to compare and check the calculation.The results show that the calculated post-peak stress-strain curves are basically consistent with the experimental curves,which indicates the correctness of the established model.With simple form,few parameters and wide applicability,the model is expected to be widely used in practical engineering deformation and stability calculation and analysis.The research has theoretical and engineering practical values.